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Comparison between the theoretical models and experimental structures of some oc tacoordinated Ln(Ⅲ)-bis-dipyridyl-bis-dichloroacetato-diaquo complexes and their phenanthroline analogues

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Journal of Rare Earths 2010年第S1期28卷 83-85页

作者： S. P. SINHA Alfredo m. SImAS Gustavo L. C. mOURA srd 6565 Willowick Pl.DaytonOHIO 45459-3005U.S.A. Departamento de Quimica Fundamental CCENUniversidade Federal de Pernambuco50590-470Recif ePEBrazil

The title complexes were modeled using the semiempirical mOPAC and the newly developed SPARKLE paramerters of the lanthanides. The calculated bond dis tances and angles agreed well with those found from crystal structure measuremen ts. This technique allows us to screen a large number of molecules and get struc tural information within a very short time.

关键词： lanthanide complex theoretical models octacoordination dipyridyl p henanthroline mOPAC SPARKLE rare earths

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Automated Spam Review Detection Using Hybrid Deep Learning on Arabic Opinions

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Computer Systems Science & Engineering 2023年第9期46卷 2947-2961页

作者： Ibrahimm.Alwayle Badriyya B.Al-onazi mohamed K.Nour Khaled m.Alalayah Khadija m.Alaidarous Ibrahim Abdulrab Ahmed Amal S.mehanna Abdelwahed motwakel Department of Computer Science College of Science and ArtsSharurahNajran UniversitySaudi Arabia Department of Language Preparation Arabic Language Teaching InstitutePrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Computer Sciences College of Computing and Information SystemUmm Al-Qura UniversitySaudi Arabia Computer Department Applied CollegeNajran UniversityNajran66462Saudi Arabia Department of Digital media Faculty of Computers and Information TechnologyFuture University in EgyptNew Cairo11845Egypt Department of Computer and Self Development Preparatory Year DeanshipPrince Sattam bin Abdulaziz UniversityAlKharjSaudi Arabia

Online reviews regarding purchasing services or products offered are the main source of users’*** gain fame or profit,generally,spam reviews are written to demote or promote certain targeted products or *** practice is called review *** the last few years,various techniques have been recommended to solve the problem of spam *** spam detection study focuses on English reviews,with a lesser interest in other *** review detection in Arabic online sources is an innovative topic despite the vast amount of data ***,this study develops an Automated Spam Review Detection using optimal Stacked Gated Recurrent Unit(srd-OSGRU)on Arabic Opinion *** presented srd-OSGRU model mainly intends to classify Arabic reviews into two classes:spam and ***,the presented srd-OSGRU model follows different levels of data preprocessing to convert the actual review data into a compatible ***,unigram and bigram feature extractors are *** SGRU model is employed in this study to identify and classify Arabic spam *** the trial-and-error adjustment of hyperparameters is a tedious process,a white shark optimizer(WSO)is utilized,boosting the detection efficiency of the SGRU *** experimental validation of the srd-OSGRU model is assessed under two datasets,namely DOSC *** extensive comparison study pointed out the enhanced performance of the srd-OSGRU model over other recent approaches.

关键词： Arabic text spam reviews machine learning deep learning white shark optimizer

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Global Warming Induced Sea Level Rise on Soil, Land and Crop Production Loss in Bangladesh

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Journal of Agricultural Science and Technology(B) 2011年第2期1卷 266-271页

作者： m. A. Hossain Soil Resource Development Institute （srd1） Ministry of Agriculture Krishi Khamar Sarak Farmgate Dhaka-1215 Bangladesh

Available data have been analyzed to assess impacts of global warming induced sea level rise on loss of soil and land resources and their implications on food security of Bangladesh. Scientists believe that because of sea level rise coastal zone of Bangladesh has already experienced noticeable impacts especially in terms of area of inundation and erosion, saline intrusion, loss of soil and land, loss of crop production in addition to migration of people from vulnerable areas. The loss of land mass and degradation of soil and land resources will adversely affect national food production and thereby food security. Sea level rise impacts are really high for Bangladesh, though the country plays insignificant role in green house gas emission. Development and implementation of adaptation policies and taking initiatives to realize those policies are the right ways to respond to sea level rise impacts in Bangladesh.

关键词： Climate change sea level rise soil and land resources adaptation policies.

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molecular modeling of the Octacoordinated Tetracarbonato-Nd(Ⅲ),[Nd(CO3)4]5-,Complex and its Nonacoordinated Fluoro and Aquo Adducts

Molecular Modeling of the Octacoordinated Tetracarbonato-Nd(...

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第六届国际稀土开发与应用研讨会

作者： S.P.SINHA Alfredo m.SImAS Gustavo L.C.mOURA srd 6565 Willowick PI.DaytonOHIO 45459-3005U.S.A. Departamento de Quimica Fundamental CCENUniversidade Federal de Pernambuco50590-470RecifePEBrazil

Carbonato complexes of the lanthanides and the actinides play an important role in the environment. In seawater,lanthanides and actinides are known to complex with the carbonate ion(CO).Depending on the concentration of the carbonate ion,the pH and the ionic strength,various species,including[Ln(CO)] are present in aqueous ***[1]and others[2,3]have shown the quantitative formation of the tetracarbonato complex,[Ln(CO)],at a pH～12. Sinha[3]observed extreme hypersensitivity of the fluorescent D→F transition in tetracarbonato complex of Eu(Ⅲ).He was also able to show[1]the presence of a difluoro adduct of Eu(Ⅲ)-tetracarbonato complex from the fluorescent lifetime ***,Sinha was not able to isolate the lanthanide(Ⅲ)-tetracarbonato complexes or the difluoro adduct in the solid state. It was of interest to investigate the structures of the octacoordinated lanthanide-tetracarbonato(Ⅰ) complexes and the fluoro and aquo adducts using molecular modeling technique and the recently developed SPARKEL parameters for all lanthanide *** semiemperical[4]approach has great advantage in screening a large number of analogous structures hundred times faster than the ab-initio methods and generating good geometry, bond lengths and bond angles. The Ln-O bond lengths of the octacoordinated(Ⅰ) complexes are listed *** values agree very well with those obtained for the bidentate carbonato complexes of the lanthanides[5].The structure of the "four-bladed propeller-shaped" complex-(Ⅰ) may be approximated as a staggered square *** calculated structure of Nd-(Ⅰ) complex is shown in ***.2 and Fig.3 show the calculated structures for the mono-fluoro and monaquo adducts. The mono-fluoro adduct is shown to have a monocapped-square antiprismatic structure with an average Nd-O distance of 2.53A and a longer Nd-F distance(2.55A).There is a slight increase in the Nd-O bond length in nonacoordinated mono-fluoro adduct in comparison to the octacoord

关键词： Lanthanide Complex Theoretical molecular models Octacoordination Tetracarbonato Complex

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